This forest plot displays 4 parallel design trials and 1 crossover study. The trials have heterogeneous results with net differences ranging from 6.5 to 26.6 percent, favoring CPAP over control. Overall, the summary net difference was 12.1 percent (95 percent confidence interval 6.4 to 17.7), P<0.001, favoring CPAP over control, with statistical heterogeneity (I-squared = 75 percent, P=0.003). The crossover study result (6.5 percent) is somewhat smaller than the results of the parallel design trials, which ranged from 8.8 to 26.6 percent.

Figure 9Meta-analysis of minimum oxygen saturation (%) in randomized controlled trials of CPAP vs. control, by study design

AHI = apnea-hypopnea index, CI = confidence interval, Fixed = fixed CPAP (continuous positive airway pressure), min O2 = minimum oxygen saturation, tx = treatment.

From: Results

Cover of Diagnosis and Treatment of Obstructive Sleep Apnea in Adults
Diagnosis and Treatment of Obstructive Sleep Apnea in Adults [Internet].
Comparative Effectiveness Reviews, No. 32.
Balk EM, Moorthy D, Obadan NO, et al.

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